. ♪ (train horn) vo: wherever our trains go, the economy comes to life. norfolk southern. one line, infinite possibilities. >>> usa! usa! >> chris: the manhunt in boston is over. but what did we learn about the terror threat and how best to protect the homeland? we are joined now by two men on the front lines here in washington, phillip mudd who spent more than a quarter censure are you at the c.i.a., the national security council and the f.b.i. and commissioner charles ramsey head of the philadelphia police department joins us from there. gentlemen, welcome to both of you. >> thank you. >> commissioner ramsey is head of the nation's fourth largest police department. what have you learned from boston? is there any way to stop what appears to have been a small domestic terrorist cell? >> well, certainly it's a challenge. i don't think anyone can say we can totally stop these attacks from occurring. but we do learn. as the incidents take place. and we take steps that we can to protect our public. >> mr. mudd, we interviewed seven years ago it turns out as a power player when